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Transient overvoltage due to lighting and changes of the power system is the main factor that may cause damage to the power system or equipment. Failing logging system and online monitoring system are not capable of well recording the transient overvoltage signal owing to shortcomings including limited sampling rate and electric structure. A new overvoltage transducer based on non-contact capacitor has been developed and it can be applied to overvoltage monitoring. The decoupling technology between different phases has been studied.

With the capability of the virtual machine monitor, a novel approach for logging system activities is designed. In the design, the guest operating system runs on the virtual machine monitor as non-privileged mode. The redirecting and monitoring modules are added into the virtual machine monitor. When a guest application is calling a system call, it is trapped and redirected from the least privileged level into the virtual machine monitor running in the most privileged level. After logging is finished, it returns to the guest operating system running in the more privileged level and starts the system call. Compared with the traditional methods for logging system activities, the novel method makes it more difficult to destroy or tamper the logs. The preliminary evaluation shows that the prototype is simple and efficient.

The Prompt Fission Neutron (PFN) uranium logging system has been used by Sandia National Laboratories for field operations for about six years; during that time, the system has been used at several exploration sites from southern Texas to Wyoming. Some of the improvements, recent changes to the system, and new applications are discussed here. A high-voltage doubler has been designed for the neutron generator which permits operation at pulse rates of up to one kHz. Other improvements in hardware have also been made. The PFN tool has been tested at moderately elevated temperatures (~93°C). The tool has been used in support of the Uranium Mill Tailings Remedial Action Program (UMTRAP) at various mine tailing sites in Colorado and Wyoming. The log interpretation model has now been completed, and a patent on the system has been issued. The tool design will be released to the National Technical Information Service, and is available for anyone to build and use; the software is also available.

A portable digital system for rapid on-line calculation of reactivity during nuclear plant physics testing has been designed and implemented. This system allows auxiliary data logging, formatting, and transmission to remote computer systems for further analysis. Provisions are made for operator displays as well as off-line computation within the system.